220 / 2019-09-01 15:07:25

Enhanced moderate-velocity impact resistance of Helicoidal Composites through Fused filament fabrication (FFF)

helicoidal composites; moderate-velocity impact; enhanced impact resistance; FDM.

计算力学在工程中的应用 > 复合材料力学

Bioinspired Composites, capable of tailoring mechanical properties by the strategy of fostering strengths and bypassing weaknesses, are vital for numerous engineering applications such as lightweight ultrahigh-strength, enhanced toughness, improved low-velocity impact resistance, wave filtering, and energy harvesting. Helicoidal Composites are ones of them. However, moderate-velocity impact study has been ignored, which occurs in auto and defense industries. Here, we report a joint experimental and theoretical study on dynamic response of helicoidal composites subject to moderate-velocity impact (20-60 m/s). Our helicoidal structures, inspired by Stomatopod Dactyl club, are fabricated using polylactic acid (PLA) by FFF in a single-phase way. The helicoidal strategy is aimed to exploit in maximum extent the axial tensile strength of filaments and make up simultaneous the shortage of inter-filament contact strength. We demonstrate experimentally that the moderate-velocity impact resistance has been enhanced efficiently as helicoidal angle and the amount of interlayers vary, which also has been confirmed by the theoretical model. Our theoretical model is based on dynamic impact mechanics of laminates. The finding reported here provides a new routine to design composites systems with enhanced impact resistance, offering a wide range of potential applications in harsh dynamic conditions.